Machine for producing and re-sharpening cutter blades



June 8, 1937. J. HANSEN 2,082,832

MACHINE FOR PRODUCING AND REHARPENING CUTTER BLADES Original Filed Aug.27, 1934 2 Sheets-Sheet 1 a I t o 5' IE3! 47 INVENTOR M ATTORNEY June 8,1937. J. HANSEN 2,082,832

MACHINE FOR PRODUCiNG AND RESHARPENING CUTTER BLADES Original Filed Aug.27, 1934 2 Sheets-Sheet 2 43 '4/ ATTORNEY Pat ented June 8, 1937 2.00ammom roa raonucmo m air-smarname coma BLADES John Hansen, Bettendorl,Iowa will!!! August 27, 1934, Serial No. 141,575 1 Renewed March 15,183'! 13 Claims. (CL 51-92) My invention has reference to a machine forproducing and re-sharpenins cutter blades, of that type which areemployed in bread slicing machines. It has more special reference to theproduction of blades provided on one of their edges with a series ofindentations or scallops. such as are set forth in my former applicationfor Letters Patent of the United States for a Method for producingcutter blades for slicing 10 machines, filed July 1, 1933, Serial No.678,631. The method referred to consists in bending a blade into acurved shape and presenting a bent portion thereof to an abrasiveelement in a plane to remove a portion of the metal of the 15 blade, andform an indentation therein of desired conformation.- The presentinvention is desiwed for the support of a blade while the several stepsof the method are being carried out, including certain features havingto do with the do adjustment of some of the parts to insure the properrelative positioning of the blade and grinding element. Means are alsoprovided for enacting the movement of a blade after the forming of oneindentation therein to a position for 25 forming another one thereof,which means includes a metering control, by means of which a propermovement of the blade supporting drum is determined. v

The above-named, and other features and ad- 3 vantages of the inventionwill be more readily understood from the following specification,

taken in connection-with the accompanying drawings, in which;

. Fig. 1 is a plan view of a machine which em 35 bodies the invention.

Fig. 2 is a detail of the ratchet-bar 39.

Fig. 3 is a detail of the ratchet-bar control mechanism.

Fig. 4 is a plan view of one of the cutter blades 40 produced by themachine. 7

Fig. 5 is a cross-section on the line 5-5 of Fig. 4.

Fig. 6 shows the blade supporting mechanism, in medial vertical section.

45- Fig. 7 is a plan view of the'blade supporting unit, detached.

Fig. 8 is an edge view thereof.

The reference number I indicates a table or bed of the machine, whichmay be supported in 50 any well known manner, and upon which is slidablymounted aplate 2, by means of guides on the lower face of said plate inengagement with tracks 3 on the table. Fixed on the plate 2 is a bearing4, in which is rotatably mounted a shaft 5, 55 on one end of which isfixed a wheel 6, 0f abrasive material. on the other end of said shaft isa pulley I, connected by a belt 8 with a pulley t on the drive shaft ofan electric motor It, also mounted on the plate 2. At the forward noedge of said plate is an ear l2, perforated and threaded to receive thethreaded end of a rod IS. the outer end of which is held rotatably in abearing II on the forward edge of the table I. On the end of the rod isa crank I5, by means of which the rod may be rotated, and by which 5movement the plate 2 can be given an adiustment forwardly or rearwardlyfor the purpose hereinafter set forth.

Another plate or carriage I6 is also mounted on the table I. formovement transversely of 10 the front of the machine, the forward edgeof said plate having a mounting I'l slidable on bearings I8 on a shaftI9 supported on the table I, and the rear part of said plate l6 beingslidable on a track 2|], also supported on the table Q I. (Figs. 1 and6.) Fulcrumed at one end of the table, as at a is a hand-lever 2|,connected by a link 22 with a post on one end of the plate l6, as at b.By means thereof the carriage can be given'a reciprocating movement onthe table.

Rockingly mounted on the plate It, as by pivotal connections at c is aframe 23, held normally from such movement by a bolt 24, supported inthe frame and in engagement with a slot in an arcuate rack 25 supportedon the plate l6. By 25 loosening said bolt the frame can be tippedupwardly or downwardly, as desired. Mounted within said frame is abearing 26, in which is rotatable a vertically disposed shaft 21, onwhich is keyed a drum 28, both shaft and. drum being in a slightlyinclined position with relation to the bed-plate of the machine. Saiddrum is partly cut away, and within the space between the ends thereofis a pair of arms 29, carried by collars 30 rotatable on the shaft 21,only one of which is shown. In the ends of said arms are pins 3| forengagement with openings in the ends of the cutter blades, for holdingthe same in position on the drum, as shown at 33 in Fig. 1. Said armsare provided with screws 34, rotatable 40 in threaded openings in saidarms, and bearing against the ends of the drum. By adjustment of saidarms the blade can be held rigidly in position on the drum while beingoperated on, and adjustments of said arms can also be made to conformthe sameto blades of diiferent lengths. The upper end of the shaft 21 isfitted with a hand-hold 35 by means of which the drum can be rotated,and by means of which it can be held from rotation while the grindingoperation is in process. The upper portion of the drum is of reduceddiameter, leaving a shoulder 38. which supports the lower edge of theblade, and aids in keeping the same in true position while the processof grinding the blade is being carried on.

In Fig. 1 the drum 28 is shown at one side, with the blade out ofcontact with the wheel 8, and inclined in position so that as the bladeis passed across the face of the wheel a portion of lo the upper edge ofthe blade will be removed. On account of the bent position of the bladethis results in the formation of an arcuate scallop as shown at 41 inFig. 4. with a flat portion or facet along the edge of such scallop.

.To accomplish this the blade supporting drum and carriage supportingthe same are given a reciprocating movement toward the left in Fig. 1and back to. the starting point. During this movement the drum isnon-rotatable, as the rotation thereof during .the grinding operationwould produce a continuous sharp edge on the blade, like a razor edge,which would not be desired. The drum 28 can be held in stationaryposition with relation to wheel during the grinding operation, but achannel would soon be worn in the wheel if this were done. After thedrum has been returned to its nonoperative position the shaft 21 isgiven a partial rotation by means of the handle 35, bringing a blankspace on the blade into positiqn for-the grinding operation. The degreeof movement of the drum and blade is controlledby means of the followingdevicesz-Rotatable on the shaft 2'! beneath the drum 28 is a ratchetdisk 31, connected with the drum so as to be movable therewith, andprovided on its periphery with k a plurality of teeth 38, engageable bya similar tooth on a bar 39, pivoted at e on a plate 40. The movement ofthe drum to the extent of one of the teeth on the disk 31 will impartthe desired amount of movement to the blade, and these movements will berepeated until the desired number of scallops are formed, whereupon theposition of the blade will be reversed, and a similar operation had onthe opposite side thereof. The plate 40 is movable on the frame 23,andis held from turning by means of a guide 4| on the lowerjside of theplate, slidable in a slot 42 in the frame. Fixed on said plate is acylinder 43, open at one end and provided thereat with slots 44 in whichthe bar 39 has lateral play. The engagement of the tooth on the bar 39with those on the ratchet disk is enforced by means of a coiled spring43a in the cylinder 43. The plate 40 is held from movement by a bolt 45passing through a slot 46 in the plate and into the frame 23. Byloosening said bolt an adjustment of the position of v the number ofsuch teeth. As a result the point at wh'lch the .drum stops for the lastcutting is more or less remote from that at which the first cutting ofthe blade was had. As a result, when a blade is removed, and a new oneplaced in position, the ratchet bar is released and the drum rotated inone direction orthe other until the bladeis brought into position forthe first grinding, whereupon the ratchet bar is again engaged with theratchet-wheel. This also has to be done when the grinding is finished onone ation must correspond very closely with that of the flrst, so thatthe scallops and points shall exactly coincide. After the reversal ofthe position of the blade, in case there is such fault in the grindingit can be corrected by turningv the drum 28 to bring the blade into anaccurate position, and acfiusting the position of the ratchet-bar toconform therewith. This will insure a proper cutting of the scallops inthe blade in which the corrections are being made, and also in otherblades of the same lot.

Drums of difierent diameters can be operated in the machine, withratchet disks corresponding therewith. A continuous grinding on thewheel 6 will result in a general wear thereof, so that from time to timean adjustment of the wheel with reference to the movement of the drummust be made. This is accomplished by movement of the plate 2 forwardly,and when a worn wheel is replaced by a larger one the plate is movedrearwardl; again. As the diameter of the wheel 6 is reduced by wear theangle of the plane of the drum 28 with reference thereto will varysomewhat, and this variation can becompensated for and corrected byadjustment of the frame 23, as before described, to vary the degree ofinclination of the drum, and present the blade to the wheel at a littledifferent angle.

If desired, the indentations can be punched or otherwise formed in'theblades, following ,which the grinding operation would be carried tory toproduce the indentations and complete the operation in the one grindingprocess.

The eflEect will be the same, whether the blade supporting drum isreciprocated with relation to the grinding wheel or the drum mountingheld in stationary position and the wheel moved with reference thereto,and in the case of the movement of the carriage. I 6 it will be obviousthat the same can be operated by mechanical power. as is done with thereciprocating carriages of standard grinding machines. When operated byhand the blades can be produced at a considerable amount of speed, andby a single operator, the right hand being used for actuating the lever22!, and the other hand in turning the shaft 21 at the end of eachmovement of the carriage.

What I claim, and desire to secure by Letters Patent, is:

1. In a machine for producing a series of adjacent scallops in one edgeof a cutter blade, the combination of an abrasive wheel and means forrotation thereof, a cutter blade support mounted in proximity to saidwheel, means carried by said support for mounting a cutter blade in apredetermined bent position with one of its edges presented to saidwheel in suitable position for the grinding thereof, means for movementof said support. to present new spaces on a blade for grindingoperations, and means for gauging the length and positions of saidspaces.

2. In a machine for producing a series of scallops of predeterminedlength and depth in the edge of a cutter blade, the combination of anabrasive element and means for rotation thereof, a drum rotatablymounted in proximity to said abrasive element, means carried by saiddrum for the support of a cutter blade in bent position and in a planefor the grinding of scallops in one edge thereof, means for giving tosaid drum and abrasive element a relative re- ,ciprocating movement,means for giving intermittent movements to said drum consecutively withsaid reciprocating movements, to, present new spaces on a blade forgrinding operations, and means for adjustment of the last named means tocorrect faults in the positioning of said spaces.

. 3. In a machine for producinga scalloped edge on a cutter blade, asupport, a grinding wheel on said support, a disk rotatably mounted onsaid support, adapted to receive-and benda cutterblade into apredetermined curvature, and pro-' vided with a segmental space in oneof its sides, arms supported in said space capable of movement to orfrom each other, and blade engaging means at the ends of said arms.

4. In a machine for producing a scalloped edge on a cutter-blade, meansfor mounting such cutter-blade in a machine, comprising a support, agrinding wheel mounted on said support, a disk rotatably mounted on saidsupport, and provided in one of its sides with a segmental space, a pairof members supported in said space and provided at their outer ends withmeans for engagement with openings in the ends of cutter-blades, andmeans for holding said members in adjusted positions, with a bladeengaged thereby held rigidly on said disk.

5. In a machine for producing a scalloped edge on a cutter blade, meansfor mounting said cutter blade in a machine, and controlling the actionthereof in said machine, comprising a, support, a grinding wheel mountedon said support, a (.iSk mounted thereon and provided with means for thesupport of a cutter blade having perforations in its ends, a ratchetwheel connected with said disk, and provided with a series of teethcorresponding 'with the movements desired to be given to the disk forsuccessive grindings, and means for engagementwithsaid ratchet wheel tocontrol the length of such'movements.

those on the other side.

7. In a machine for producing a series of scallops in one edge of astrip of metal, a frame, a-

,grinding element mounted thereon, a support mounted in proximity tosaid element for reciprocation transversely thereof, a fixture carriedby said support adapted to receive and bend such strip of metal into adefinitely curved position, means for presenting said fixture tothegrinding element in an inclined position to cause a grind-' ingaction on the edge of said strip, means for varying the inclination ofsaid fixture with reference to the grinding element, and means foradjustment of the position of said grinding element with relation tosaid fixture. 1

8. In a machine for producing a series of seal lops in one edge of astrip of metal; a frame, a grinding element mounted thereon, a supportmounted in proximity to said element'for reciprocation on a linetransversely thereof, a fixture carried by said support adapted toreceive and bend a strip of metal into a definitely curved position,means for presenting said fixture to the grinding element to produce agrinding action on the edge of a strip of metal carried thereby, meansfor reciprocating said support, to produce a scallop in the edge of saidstrip of metal, means for varying the position of said fixture withrelation to said grinding element, means for adjustment, of the positionof said grinding element with rela on to the line of movement of saidfixture, a d means for effecting a change in the position of the cutterblade to present successive blank spaces thereon to said grindingelement.

9. In a machine of the class described, a cutter blade holding mechanismcomprising a disk rotatably ounted and provided with a fragmentary bladeb nding segment and a segmental blank space, blade engaging elements insaid blank space, a metering mechanism operatively connected with saidmechanism for determining the degree of movement thereof in presentingsuccessive blank spaces on a cutter blade to an abrasive action and anabrasive means supported adjacent .to' said disk.

10. In a machine for forming scallops in the edge of a cutter blade, ablade holding mechanism comprising a circular member provided with afragmentary blade bending portion, and a segmental blank space at theends thereof, blade engaging elements in said blank space, means foradjustment of said elements for use with blades of different lengths andan abrasive tool in proximity to said circular member.

11. In a machine for forming scallops in the edge of a cutter blade, ablade holding mechanism comprising a disk having an abutment for thesupport of a blade in arcuate position, establishing the position ofsuch blade for grinding said scallops, means carried by said disk forholding such blade in fixed position thereon and an abrasive elementoperatively supported in ,proximity to said disk.

12. In a machine for producing and resharpening a series of scallops inan edge of a strip of metal, a grinding element, a support mounted inproximity to said grinding element, a fixture carried by said support,adapted to receive and bend said strip of metal, means for bringing saidfixture and the grinding element into grinding relation with said stripin an inclined position to the grinding element to cause a grindingaction on the edge of the bent strip of metal, means for intermittentlymoving the strip with respect to the grinding element, wherebysuccessive scalgagement with the wheel, whereby successive JOHN HANSEN.

